The effects of a choice test between food rewards and human interaction in a herd of domestic horses of varying breeds and experiences

Exploring the induction and measurement of positive affective state in equines through a personality-centred lens

There is increasing focus on how to induce and measure positive affective states in animals and the development of social license to operate has brought this to the forefront within equestrianism. This study aimed to utilise a range of methods to induce and measure positive affect in horses in real-world settings. Twenty healthy horses were scored for personality, exposed to four induction methods (wither scratching, high value food provision, positive reinforcement training and the addition of an affiliative conspecific), and data collected on their behaviour (QBA and ethograms) and physiology (heart and respiratory rate, heart rate variability, eye and ear thermography and salivary cortisol). Analyses identified potentially sensitive and specific behavioural (ear and eye position, QBA items, frustration items) and physiological (RR mean, HF power, LF power, LF/HF ratio, mean HR, RMSSD and pNN50) measures of affective state across the four quadrants of core affect. Individual difference effects were found, and personality traits such as unfriendly, nervous and unresponsive were associated with differing responses to induction stimuli indicating that all four induction stimuli are potentially useful for inducing positive affect depending on their salience to the individual. Research measuring and inducing positive affect in animals rarely considers personality, but this study underscores its importance. The dimensional approach taken allowed for assessment of the broad arousal and valence components of affect without ascribing measures to discrete emotions. Accurate, real-world measures of affect could benefit 116 million equines globally, and exploring ways to promote positive affect in horses can significantly enhance their welfare.

Inducing and measuring positive affective state in domesticated equines: A Delphi consultation

Over the last twenty years the definition of good animal welfare has advanced from the 'absence of negative welfare states' to the aim of identifying the presence of positive welfare states; however, research on positive animal welfare is relatively new. Consequently, through expert consultation, this study aimed to synthesise knowledge regarding domesticated equine emotional state, specifically methods to induce and measure positive affective states, which could be of significant benefit to equine welfare across sectors. A Delphi consultation of experts in the field of equine behaviour, welfare and affective state was undertaken to derive consensus agreement on definitions used when considering positive affective state in equines and methods suitable for inducing and measuring these states within experimental investigations. Ninety-three international experts participated in a robust three-round Delphi consultation with data gathered analysed qualitatively (thematic analysis) and quantitatively (ranking data, consensus benchmarks and Content Validity Index (CVI) / Content Validity Ratio (CVR) analyses). Retention rates were high (78 %), and consensus (minimum 70 % agreement) was reached within Round three of the consultation. Nineteen methods for inducing positive affect reached consensus (provision of high value food, an affiliative companion and a substrate to roll in where the highest ranked), and twelve behavioural (assessment of body language, facial actions and horse-horse interactions were ranked highest) and three physiological (evaluation of heart rate, heart rate variability and respiratory rate) variables for measuring positive affect also reached consensus. This consultation highlights several important considerations surrounding the induction and measurement of positive affective state in equines, including consideration of the individual's personality and individual preference within any measures of affective state. We therefore recommend that establishing individual preference should be a prerequisite of research into positive affective states. It is anticipated that the results of this study can be used to provide new direction for research on positive affective states by providing expert agreed methods and measures for policy and practice through expert agreed approaches to induce positive affect in horses.

Exploring the relationship between horse-owner attributes and their approach to horse training

The way horses are trained has implications for equine welfare and training success, yet little is known about the factors that influence horse-owners' choice of training approach (TA). Limited understanding in this area will hinder the development and dissemination of evidence-based training advice to owners. Consequently, this study aims to identify demographic and attitudinal factors that influence horse-owner TA selection. A 22-question online survey collected information from 1,593 horse-owners about their demographics, equestrian activities, goals and beliefs. Participants rated how likely they were to use six different horse TAs on a five-point scale. Multinomial regression analysis and Spearman's correlation coefficients were used to identify factors associated with their likelihood of using each TA. Several factors were associated with reported TA use, including age, gender identity, goals, activities, industry role and whether they had training in animal behavior. Beliefs about equine sentience, cognitive ability and whether science should inform horse training correlated with likelihood of applying aversives. This study provides insight for further research and development of educational strategies to reduce the use of training approaches that may compromise equine welfare.

Forced Handling Decreases Emotionality but Does Not Improve Young Horses' Responses toward Humans and their Adaptability to Stress

Horses are often still exposed to stressful or inadequate conditions and difficult relationships with humans, despite growing concerns about animal welfare. In the present study, we investigated the impact of different approaches of short-term handling sessions on young Lusitanian horses raised on a high-breed farm, specifically on their later adaptability to humans and stressful environments. Thirty-one foals (3 months old ± 15 days), from both sexes, were separated into three groups, one submitted to 3 consecutive days of handling sessions (Int-H), another to one handling session each month for 3 months (Month-H), and one left undisturbed (control). At 8 months old ± 15 days, all foals were evaluated during behavioral tests (restraint in a stock and forced-person test). Evaluations were based on behavioral observations and physiological assessments. The handled foals (Int-H and Month-H) reacted less to being isolated and restrained and better tolerated human contact and veterinary procedures than the control ones. The handled foals displayed less evasive and negative behaviors toward human approach, but also sought less human contact and did not interact, regardless of the handling timeframe. All animals displayed signs of stress when restrained in the stock, with increased neutrophil counts and CHCM levels in the blood, and no differences in metabolic (CK and LDH) and other hematological parameters. The neutrophil-lymphocyte ratio was significantly higher (p < 0.05) in handled foals than in control ones, suggesting low standards of welfare. Our data suggest that early forced handling decreases fearfulness in new environments; however, it does not improve the horses' relationship with humans, and it decreases welfare.

The Role of Comparative Psychology in the Training of Veterinarians

This article highlights some of the advantages that comparative psychology offers the veterinary student and veterinary education generally. Comparative psychology is the oldest of the social sciences and, as such, has accumulated over three centuries of experience in such areas as research design, animal-human interactions, and animal behavior. To establish whether comparative psychology is taught in veterinary schools, we survey all course catalogs of U.S. veterinary schools. None of the schools surveyed offered a course in comparative psychology, and inconsistencies were noted among the schools in regard to courses in animal-human interaction, animal behavior, and ethics. Suggestions are provided on how to incorporate principles of comparative psychology in veterinary education at both the undergraduate and graduate levels.

Moving toward Fear-Free Husbandry and Veterinary Care for Horses

Husbandry and veterinary procedures have the potential to generate fear and stress in animals. In horses, the associated responses can pose a significant safety risk to the human personnel involved in the procedure, as well as to the animal itself. Traditionally, physical restraint, punishment, and/or threat of an aversive, have been the most common strategies used to achieve compliance from the horse. However, from a welfare perspective, this is less than ideal. This approach also has the potential for creating a more dangerous response from the horse in future similar situations. When caring for companion animals, and captive animals within zoological facilities, there has been a steady transition away from this approach, and toward strategies aimed at reducing fear and stress during veterinary visits and when undertaking routine husbandry procedures. This review discusses the current approaches to horse care and training, the strategies being used in other animal sectors, and potential strategies for improving human safety, as well as the horse's experience, during husbandry and veterinary procedures.

Reinforcer efficacy of grain for horses

Positive reinforcement is becoming more common in horse training. Identifying effective reinforcers is critical for training success. The aim of this study was to determine relative reinforcer efficacy of different grains. Four horses learned to muzzle touch a target, after which they were tested using a progressive ratio schedule of reinforcement with different grains as the consequence. Break points were used to determine relative reinforcer efficacy of each grain and were also converted into unit price per kilocalorie to determine if caloric value impacted reinforcer efficacy. Condition 1 compared three textured grains that spanned industry-accepted standards of low to high nonstructural carbohydrate content. Condition 2 compared three pelleted grains that similarly differed in nonstructural carbohydrate content, comparable to Condition 1, but that had a different texture than those of Condition 1. Finally, Condition 3 directly compared one grain each from Conditions 1 and 2. Results showed overall little difference in reinforcer efficacy or unit price between grains but found that all grains tested functioned as reinforcers for the horses. This suggests that a range of commercially available grains can maintain behavior and therefore be used for training. We also identified possible extraexperimental factors that impact reinforcer efficacy.

The Effect of Human-Horse Interactions on Equine Behaviour, Physiology, and Welfare: A Scoping Review

Human-horse interactions (HHIs) are diverse and prominent in the equine industry. Stakeholders have an invested interest in making sure that HHIs are humane. Assessment of equine welfare goes beyond physical health and includes assessment of the emotional state of the animal. HHIs can have a permanent effect on human-horse relationships, thereby influencing welfare. Therefore, an understanding of the horse's affective state during HHIs is necessary. A scoping review was conducted to: (1) map current practices related to the measurement of HHIs; (2) explore the known effects of HHIs on horse behaviour and physiology; and (3) clarify the connection between HHIs and equine welfare. A total of 45 articles were included in this review. Studies that used both physiological and behavioural measures of equine response to human interactions accounted for 42% of the included studies. A further 31% exclusively used physiological measures and 27% used behavioural observation. Current evidence of equine welfare during HHIs is minimal and largely based on the absence of a negative affective state during imposed interactions. Broadening the scope of methods to evaluate a positive affective state and standardization of methodology to assess these states would improve the overall understanding of the horse's welfare during HHIs.

Enhanced Understanding of Horse-Human Interactions to Optimize Welfare

Horses (Equus caballus) have been domesticated for millennia and are regularly utilized for work, sport, and companionship. Enhanced understanding of human-horse interactions can create avenues to optimize their welfare. This review explores the current research surrounding many aspects of human-horse interactions by first highlighting the horse's sensory capabilities and how they pertain to human interactions. Evidence exists that suggests that horses can read humans in various ways through our body odours, posture, facial expressions, and attentiveness. The literature also suggests that horses are capable of remembering previous experiences when working with humans. The interrelatedness of equine cognition and affective states within the horse's umwelt is then explored. From there, equine personality and the current literature regarding emotional transfer between humans and horses is examined. Even though horses may be capable of recognizing emotional states in humans, there remains a gap in the literature of whether horses are capable of empathizing with human emotion. The objective of this literature review is to explore aspects of the relationship between humans and horses to better understand the horse's umwelt and thereby shed new light on potential positive approaches to enhance equine welfare with humans.

From the Horse's Perspective: Investigating Attachment Behaviour and the Effect of Training Method on Fear Reactions and Ease of Handling-A Pilot Study

The study investigated equine responses to novelty and handling, aiming to reveal whether horse-human relationships reflect criteria of an attachment bond. Twelve adult Standardbreds were subjected to a fear-eliciting test (novel objects presented close to two humans) and a handling test (being led passing novel objects) to study attachment-related behaviours and ease of handling. The tests were performed both before (pre-test) and after (post-test) horses had been trained by the same female handler (10 sessions of 15 min). Horses were assigned to three groups of four, each of which underwent different operant conditioning protocols: negative reinforcement (NR; pressure, release of lead, and whip tap signals) or combined NR with either positive reinforcement using food (PRf) or wither scratching (PRs). Results showed that neither familiarity of the person nor training method had a significant impact on the horses' behavioural responses in the post-tests. However, horses showed decreased heart rates between pre- and post-tests, which may indicate habituation, an effect of training per se, or that the presence of the familiar trainer served to calm the horses during the challenging situations. There were large individual variations among the horses' responses and further studies are needed to increase our understanding of horse-human relationships.